Zcash completed its NU6.2 hard fork after privately coordinating an emergency response to a critical Orchard forging vulnerability that could have allowed invalid state transitions, double-spending and potentially undetectable counterfeit or extra-minted ZEC within its shielded pool. Researcher Taylor Hornby discovered the flaw on May 29, 2026 while conducting protocol security research for Shielded Labs, and the Zcash Foundation said engineers confirmed it within hours. A revised emergency soft fork activated on June 2 at block height 3,363,426 to reject Orchard transactions and blocks, and the NU6.2 hard fork activated on June 3 at block height 3,364,600 to restore Orchard with a corrected circuit. The Foundation said there was no evidence of exploitation, no unauthorized value creation, no impact to user privacy and no breach of the 21 million ZEC supply cap, while also noting Orchard’s privacy means it cannot be cryptographically proven whether the flaw had been exploited before the fix. Separately, Arthur Hayes said he sold all his ZEC because extra minting appears very unlikely but cannot be ruled out with complete cryptographic certainty.